Your party must help the guards to retake the Great Northern Wall by pushing the Charr invasion back. Proceed forward until you sight the wall. Eventually, you will meet Siegemaster Lormar who will brief you how to recover and use trebuchets.

To make the siege mechanisms operable again, you need to salvage other Wrecked Catapults and use their parts to fix the one near Lormar. Each of the needed pieces are indicated in the wiki-map. Use the ALT key to search for Wrecked Catapults and click on them to obtain a usable part. Pick them up one by one and deliver them to Lormar by talking to him.

Once the trebuchet is fixed, use the lever once to charge it first and a second time to fire it. Repairing the trebuchet is not requiered to complete the mission, so high level players can skip this step and charge in.

Continue ahead and you will find another trebuchet - this one doesn't need repairing and aims towards a large crater, which Charr patrol out of. Players may find no use for this tool until foes get closer. (If the player is quick enough, they can quickly activate the trebuchet and kill the final Charr boss to complete the mission, before the Charr run away). Shortly after the player approaches the trebuchet, all enemies will scatter from the blast point.

Charr that survive the impact can be left alone as long as they don't interfere with the path leading to the boss and its group. Killing them completes the mission.

To gain the bonus, your task is to find Trooper Deeter Saberlin, who can be seen while proceeding with the mission's main objectives and only takes a minor detour (point 2).

Master Armin Saberlin is the NPC that provides this task, he joins your party early in the mission (point 1A) and will follow you up to the large ruined wall (point 1B). After clearing the mob with the boss, you can talk to him to activate the bonus if he is still alive; however, it actually does not matter if he survives or not - performing the task is enough to complete the bonus.

Only the first half presents difficulty, after the bonus it becomes much easier. The most problematic group is immediately when you start - the weak NPCs will be under attack from several groups of Charr. There is always a visible stationary group, but two other patrol groups far behind them. Those who naively engage the standing group will soon be overwhelmed by the additional forces. To avoid this, send a lure character as bait and finish the stationary group far from its spawn point. Then move slowly to face the patrols which are scripted to push forward with the invasion. The ascalonian allies, all six of them, may survive the fights but wait until their healthbar fully regenerate to continue ahead or you will lose valuable support. When facing the Charr Stalkers, use walls to obstruct projectiles - minimizing damage against your party from Ignite Arrows, and spread out if attacked in open areas.

At the second half while repairing the trebuchets, there will be groups with two Charr Fire Callers. Once again use a lure so they cast Meteor Shower away from your backliners and only then engage.

After completing this mission, your party will be taken to Frontier Gate.

Complete exploration of this mission contributes approximately 0.8% to the Tyrian Cartographer title.

Bug. If the boss and its mob (that are encountered at point 1B on the map) are not killed, the remaining allied NPCs (Ascalonian Warriors, Master Armin Saberlin, Ascalon Militia, Ascalonian Rangers) will continue to follow the party leader through the entire mission and Master Armin Saberlin will not offer the bonus objective (which is not required to complete the bonus). This makes the mission easier, since the NPCs will continue to fight alongside your party instead of stopping at point 1B.

Bug. Sometimes the soldier that is captured with Trooper Deeter Saberlin is stuck in the entry of the prison, preventing you from talking to Deeter Saberlin to complete the bonus.